Small And Large

Small and large changes in disputes between gradualism and saltationism underlies the debate on small changes or big changes. Those who have postulated major changes have done so because they hardly have considered a chain of small changes could lead to the acquisition of certain organs and sophistication present in living things today. On the other hand, supporters of small changes (currently it is accepted that life evolves through small changes) understand that major changes, based on these genetic errors, would hardly be viable (since the current paradigm, the changes would correspond to random mutations , errors in DNA replication). He was a physicist, Fred Hoyle, who provided the best metaphor to use this difficulty: In a junkyard are all the bits and pieces of a Boeing 747, loose and messy. It happens that a typhoon is battering the junkyard.What is the probability that after we find a 747 fully assembled and ready to fly It is so small it is negligible, even if the typhoon blew in so many scrap yards that fills the Universe. Fred Hoyle, The Intelligent Universe. Hoyle wanted with this metaphor to describe the difficulty which may arise through random changes complex elements that act synergistically as in the case of a “simple” molecule or the source itself life. He described the metaphor of monkeys trying to write a Shakespeare play, both metaphors were answered by Richard Dawkins, mainly in his book The Blind Watchmaker, by replacing these big changes by small cumulative changes fixed by natural selection. Popper, for this difficulty, in 1972 provided a solution without avoiding a synergy irreducible and without departing from Darwinian gradualism. Simplified the problem in the metaphor of the evolution of an aircraft and its autopilot.From nothing will enhancements on the plane if they are not accompanied by new encroachments on autopilot, even in cases may be cotraproducentes. Suggests that first they will small changes in the aircraft structure to be accompanied by small changes in the logic of the autopilot, otherwise, a development first of the autopilot instructions lead to disaster. We, therefore, the first result: if we start from a dualism in which body are perfectly balanced structure of central provision of executive control and structure controlled, then it seems likely that mutations in the structure of central provision to be a bit less lethal than mutations in the executive controlled (even potentially favorable). Our second key result is the following.Once a new purpose, tendency or disposition, a new skill or way of behaving has evolved into the central file structure, this fact will influence the outcome of natural selection, so that mutations that were previously unfavorable (though potentially favorable) are indeed favorable provided that support the recently established trend. Popper, Objective Knowledge. An evolutionary approach. Margulis simbiog tica defends his theory of evolution of life through discrete steps being its proposed acquisition of a model genomes qualitative changes in body: “The species are caused by inheritance of acquired genomes, together with their reproductive rebellions within the host genome. That’s how come higher taxa such as genera, families and others. ” This acquisition sets of genomes may appear to solve the problems involved in the development of specific organs and apparently irreducible life.Mainly bacteria, would be the breeding ground of complex organs. However, John Maynard Smith and Szathm ry E rs not say: “The motorcycle is a symbiosis between the bicycle and the internal combustion engine. It works perfectly, if one likes this kind of thing, but someone had to invent the bicycle and internal combustion engine. The symbiosis is not an alternative to natural selection, rather it is the reverse: we need a Darwinian explanation of the symbiosis. “